Current Position: 42 03S / 027 34W
24 hour progress: 130nm, 5.4kts avg SOG. Overall progress for the passage is 1,576nm, approximately 1,923nm left to go via a great circle route to St Helena.
Yesterday we sailed the whole day through a variety of winds. We started the day broad reaching on a port tack with 1 reef in the main and a full genoa. We ended the day close reaching on a starboard tack with 2 reefs in the main and a full genoa. Through the day we gybed and moved from a broad reach up to a close reach on the starboard tack. This means that everything gradually shifted back again from starboard to port, as all other things being equal, the boat heels over more the closer to the wind that you sail. Not to worry we will tack again at some point and everything will slide the other way again. It keeps us all busy trying to find secure places for things and randomly having something new come loose—often making a loud noise when someone is trying to sleep. Most interesting are the small items that turn up after having disappeared over time.
We should be out of the light airs of the high for a bit, until the next one sets up. This means stronger winds for the next couple of days. We did well for course with yesterday's changing winds with either being on our desired NE course or going a bit east or north. All basically the "right" direction. The winds were largely light and remained a bit variable. So our speeds were up and down as well. But the seas stayed calm and the sailing was good.
Most of the day was spent troubleshooting our Watt&Sea hydrogenerator and contingency planning. W&S is one of our favorite, simplest to use and most dependable pieces of gear. When we are sailing well she pumps out power. This allows us to run "Nike" our electrical (hydraulic ram) Nke autopilot, the radar and the refrigerator on max cooling without a drain on power, plus all the electronics and device chargers. W&S is basically a propeller on an arm that has a generator inside. We drop the propeller arm in like a small centerboard with its pivot on our stern; as it's propeller spins it generates power that travels through an electrical cable to our charging bus.
From the indications that we had seen, it seemed like she was no longer turning at slow speeds. We decided to draw on the propeller hub so that we could maybe verify if the prop was spinning in the turbulent water behind the stern. It was clear that at 5kts boat speed the prop was not spinning. So, we pulled the arm up and worked on trying to set up our wind vane autopilot. As Nike is so reliable and steers so well, we have the Windpilot wind vane as a backup for long passages, but have never really used her much. The problem with Nike is that she does use power. So, most of yesterday was spent trying to get the Windpilot successfully steering. This is part engineering, and part art. We were not especially successful at getting her to hold course for very long despite having the boat properly trimmed. Something is just not quite right—probably the sailors. However, after a few hours of frustrating work and some lunch the boat speed was back up over 6kts again. So we decided to try W&S. It seems above 6 or 6.5kts boat speed she generates power! So we changed our tactics and have been managing the gain on Nike to limit how much power she is using balanced with wind and boat speeds. More gain for more corrections and using more power when we have boat speed, are making power and require more steering inputs. Less gain when we are slower, need less input and are not making power. So far this is working and we recharged our batteries decently overnight. The other ways that we make green power are solar and wind. Solar didn't provide much yesterday with the cloud cover and the winds were a bit light and quite variable. The wind generator prefers consistent winds above 15 or 20kts, and going downwind in 15kts was only giving the wind generator about 10kts over the blades.
Anyway, a challenge to be sure. The manufacturer seems to recommend a depot service interval on the W&S sealed generator every 2 years/20k nm which we have obviously exceeded. We feel like it maybe isn't turning quite as freely as it should out of the water as well. We have a couple of other ideas to try to further troubleshoot as conditions permit and an email out to the manufacturer. We will see how it goes. In the meantime, we are managing with what we have and will keep trying to learn and practice the art of wind vane steering as conditions permit.
In yesterday's bird watching, we had more birds again with the occasional flock packs of prions. We continue to enjoy trying to identify the different albatrosses that circle past. We seem to have a variety that visit.
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